The Definition of Density

Warm-up

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Describing Density

... the word equation ...

$$\text{density}=\frac{\text{mass}}{\text{volume}}$$

... the algebra ...

$$\rho =\frac{m}{V}$$

• where:
• $\rho$ is the density of the material in kilograms per cubic metre, $kg/m^3$ or $kg{m}^{-3}$;
• $m$ is the mass in kilograms, $kg$;
• and
• $V$ is the volume in cubic metres, $m^3$.

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The Rearrangements.

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Videos and Questions

Density Video

Practice Questions

Textbook Exercise

(Care of corbettmaths.com)

Density RAG

(Care of www.piximaths.co.uk)

As part of compound measures:

Speed and Density:

Exam Questions

Compound Measures Questions Booklet

Solutions

(Care of www.mathsgenie.co.uk)

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In general density can be thought of as:

$$\mathrm{density}=\frac{\mathrm{quantity}}{\mathrm{region}}$$

The quantity could be any amount of something of interest, e.g, mass, number of individuals, etc.

The region is quite often three dimensional, i.e., a volume, but it could be, however, an area or a length.

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See also:

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Experimental Determination of Density

To experimentally determine the density of an object, the mass must first be measured, typically using a top pan balance or a similar device. The volume is then determined depending on the nature of the object. For regular-shaped objects, dimensions can be measured with a ruler, while irregularly-shaped objects require tools like a measuring cylinder or a eureka can. With both mass and volume known, the density can be calculated using the density formula.

Further details on the determination...

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Further Reading

Nuclear Densitometry
(care of en.wikipedia.org)